-d^2-12d+4=-6d^2

Solution for -d^2-12d+4=-6d^2 equation:

-d^2-12d+4=-6d^2

We move all terms to the left:

-d^2-12d+4-(-6d^2)=0

We add all the numbers together, and all the variables

-1d^2-(-6d^2)-12d+4=0

We get rid of parentheses

-1d^2+6d^2-12d+4=0

We add all the numbers together, and all the variables

5d^2-12d+4=0

a = 5; b = -12; c = +4;
Δ = b2-4ac
Δ = -122-4·5·4
Δ = 64
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$d_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$d_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{64}=8$
$d_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-8}{2*5}=\frac{4}{10}
=2/5
$
$d_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+8}{2*5}=\frac{20}{10}
=2
$